P0412 OBD-II Trouble Code: Secondary Air Injection System Switching Valve A Circuit Malfunction

Our certified mechanics come to you · Get a fair and transparent estimate upfront

Red-stars EXCELLENT RATING ON

Cost of diagnosing the P0412 code

P0412 is a diagnostic trouble code (DTC) for "Secondary Air Injection System Switching Valve A Circuit Malfunction". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $114.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $20.0 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.

Cars Estimate Credit towards follow-up repair Earliest Availability
Ford $114.99 $20.0
Toyota $114.99 $20.0
BMW $124.99 $20.0
SCHEDULE P0412 DIAGNOSTIC Get a fair and transparent estimate upfront

P0412 code definition

Secondary Air Injection System Switching Valve A Circuit Malfunction

What the P0412 code means

P0412 is an OBD-II generic code that the engine control module (ECM) got input from the air injection system driver that the air pump or air switching valve has malfunctioned with an open or short circuit.

What causes the P0412 code?

  • The air injection switching valve voltage is too high indicating an open circuit.

  • The air injection switching valve voltage is too low indicating an short circuit.

  • The ECM sets the code from diagnostic inputs from the air injection system driver.

What are the symptoms of the P0412 code?

  • The Check Engine Light will be illuminated and the code is set in ECM memory and freeze frame.

  • The air injection system pump may not come on.

  • The engine may not have any drive symptoms except a check engine light is on.

How does a mechanic diagnose the P0412 code?

  • Scans codes and documents the freeze frame data in order to verify the problem

  • Clears the engine codes retest the air injection system for proper operation

  • Tests the air injection switching valve is controlling the air injection pump operation during tests

  • Checks the resistance of the air injection pump and air injection switching valve

  • Checks the air injection pump for proper voltage between the pins of power and ground

Common mistakes when diagnosing the P0412 code

  • Not checking for proper battery voltage above 8 volts to the air injection pump before replacing the pump for no air pumping out of it

  • Not checking the air injection pump power relay for burnt wire connections before replacing a bad air injection pump or air switching valve

How serious is the P0412 code?

  • The air injection pump system is to help lower the emissions coming out the exhaust and can cause the vehicle to fail emission testing.

  • The Check Engine Light being on causes the vehicle to fail emission testing.

  • The air injection pump should not cause any drive symptoms other than a Check Engine Light.

What repairs can fix the P0412 code?

  • Replacing the air injection pump and power relay
  • Replacing the air injection switch valve
  • Repairing the wiring to the air injection pump power relay connection

Additional comments for consideration regarding the P0412 code

Code P0412 is a problem with the air injection system driver in the ECM cannot turn on the air pump to test it during startup. A shorted air injection pump circuit can short out the air injection driver in the ECM and should be considered when diagnosing the problem.

Need help with a P0412 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

Check Engine Light
trouble codes
P0412

No more waiting rooms! Our mechanics will come to you to diagnose and fix the P0412 code.

SCHEDULE P0412 DIAGNOSTIC
Get a $20 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(7400)

Rating Summary
6879
249
58
41
173
6879
249
58
41
173
 at YourMechanic

David

13 years of experience
393 reviews
David
13 years of experience
Chevrolet Malibu L4-2.4L - Check Engine Light is on Inspection - Marietta, Georgia
He explained everything to me in detail on what I needed to know about my car. Definitely recommend him for getting the job done.
 at YourMechanic

Raymond

37 years of experience
402 reviews
Raymond
37 years of experience
Toyota Camry L4-2.2L - Check Engine Light is on - Las Vegas, Nevada
Raymond did a great job however I was charged for two hours labor and he was only here less than 45 minutes. should I expect this on future appointments with your mechanic ?
 at YourMechanic

Shane

17 years of experience
217 reviews
Shane
17 years of experience
Volkswagen EuroVan V6-2.8L - Check Engine Light is on Inspection - Austin, Texas
Arrived on time. Explained the issues he found and how he will fix it. I have parts on order and will schedule an appointment to have Shane install the parts when they arrive.
 at YourMechanic

Kanstantsin

19 years of experience
51 reviews
Kanstantsin
19 years of experience
Ford F-150 V8-4.6L - Check Engine Light is on Inspection - Littleton, Colorado
Kanstantsin arrived early. Was very courteous and professional. Will highly recommend to anyone. Thank you Kanstantsin.


More related articles

P0264 OBD-II Trouble Code: Cylinder 2 Injector Circuit Low
P0264 P0264 code definition Cylinder 2 Injector Circuit Low What the P0264 code means This diagnostic trouble code (https://www.yourmechanic.com/article/what-is-the-on-board-diagnostics-obd-system) indicates that the powertrain control module (https://www.yourmechanic.com/article/what-is-a-vehicle-s-electrical-control-unit) has detected a lower reference voltage from the fuel injector on the number 2...
P2534 OBD-II Trouble Code: Ignition Switch Run/Start Position Circuit Low
P2534 P2534 code definition A P2534 trouble code indicates that the PCM has detected a problem in the ignition switch run position circuit. Codes related to a P2534 trouble code include: P2530, P2531, P2532, P2533, P2535, P2536, P2537, and P2538....
P0431 OBD-II Trouble Code: P0431 Warm Up Catalyst Efficiency Below Threshold (Bank 2)
P0431 means there is a failure in the catalytic converter due to too much or little fuel intake or contamination from engine oil.

Related questions

oxygen sensor
This is correct in that sometimes the Check Engine Light will stay on. A qualified mechanic should be able to reset this after replacing the oxygen sensor (https://www.yourmechanic.com/services/oxygen-sensor-replacement). I would suggest having an expert, like one from YourMechanic, come to...
Flashing CEL
The codes you recorded, P0304 (https://www.yourmechanic.com/article/p0303-obd-ii-trouble-code-cylinder-3-misfire-detected-by-spencer-clayton), P0171 (https://www.yourmechanic.com/article/p0171-obd-ii-trouble-code-system-too-lean-bank-1-by-andrew-quinn), P0301 (https://www.yourmechanic.com/article/p0301-obd-ii-trouble-code-cylinder-1-misfire-detected-by-jamahl-walker), P0300 (https://www.yourmechanic.com/article/p0300-obd-ii-trouble-code-random-multiple-cylinder-misfire-detected-by-jamahl-walker), all pertain to engine misfiring. The flashing of the Check Engine Light (https://www.yourmechanic.com/services/check-engine-light-is-on-inspection) signifies that the misfiring is "active" (ongoing) and consequently you should try to get the...
I have a 2010 Nissan altima it's given me a p1717 code and does not move can anyone help
I have checked this code and there is not a listing that code P1717 applies to this vehicle. You will need to have the computer scanned again and verify the codes stored. Once you get the correct code then let...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com